condition mean min max ZT0-3 2.2792399999999997 2.1488899999999997 2.4095899999999997 ZT4-7 0.872379 0.872379 0.872379 ZT8-11 0.33758699999999997 0.33758699999999997 0.33758699999999997 ZT12-15 0 0 0 ZT16-19 1.382045 1.382045 1.382045 ZT20-23 1.621025 1.621025 1.621025